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Suppose a chemist starts with an aqueous buffer that contains 0.05 mol of HCN and 0.07 mol of NaCN in a total volume of 1.00 L. What is the pH after 0.03 mol of OH- is added to the buffer?  a. 9.01 b. 9.46 c. 10.92 d. 10.01 e. 8.61

Which one(s) of the following substances is (are) a weak base in aqueous solution?   1. IO-       2. OH-       3. C2O4 -2        4. NH3       5. HCHO2   a. 2 only b. 1 and 4 only c. 1, 2, 3, and 4 only d. 4 and 5 only e. 1, 3, and 4 only

Classify HClO as a strong base, weak base, strong acid, or weak acid, and then answer the following question. What is the pH of a 0.07 M HClO (aq) solution? a. 1.2 b. 8.7 c. 4.3 d. 9.7 e. 5.3

What is the charge of Cr in the complex [Cr(CN)2(NO2)2]- ? a. +5 b. 0 c. +3 d. +1 e. -1   Tables.pdf Periodic Table with New Elements.pdf

Classify HNO3 as a strong acid, weak acid, strong base, or weak base, and then answer the following  question. Suppose 0.0139 g of HNO3 is dissolved in 625 mL of aqueous solution. What is the pH?   a. 1.65 b. 3.66 c. 6.45 d. 3.45 e. 4.65

Which of the following compound(s) is (are) ionic? 1. BaBr2          2. Fe2(CO3)3        3. Sr(OH)2         4. SO2   5. C6H12O6   a. 1 and 2 only b. 1, 2, and 3 only c. 4 and 5 only d. 1, 2, 3, and 4 only e.  All are ionic

What is the solubility of BiI3 (s) (in g/L) in a solution that contains 0.90 M I- (aq)? a. 1.1 x 10-18 g/L b. 2.4 x 10-17 g/L c. 5.3 x 10-16 g/L d. 1.8 x 10-16 g/L  e. 6.6 x 10-16 g/L    Tables.pdf Periodic Table with New Elements.pdf

For the following reaction: 2N2O5(g) 

Write the correct dissolving equation for Ag2CrO4 (s) on scratch paper, and then answer the following question. Which of the following is the correct Ksp expression for the dissolving of Ag2CrO4 (s)?   a.  Ksp =[Ag2Cr2+][O42-] b.  Ksp =[Ag+][CrO42-] c.  Ksp =[Ag22+][CrO42-] d.  Ksp =[Ag+][Cr+6][O2-]4 e.   Ksp =[Ag+]2[CrO42-]

The Ksp of Ca3(PO4)2 is 1 x 10-33.   What is the solubility in moles per liter (mol/L) of Ca3(PO4)2 (s) in a 0.01 M Ca(NO3)2 (aq) solution? (Note: The molar mass of Ca3(PO4)2 is not needed in this problem, which asks for moles per L.)   a. 3.2 x 10-14 mol/L b. 3.0 x 10-15 mol/L c. 9.8 x 10-8 mol/L d. 1.6 x 10-14 mol/L e. 5.0 x 10-32 mol/L